QIQIHAR, Heilongjiang — Zhalong National Nature Reserve in Northeast China's Heilongjiang province is the largest reed marsh wetland in the country.

With an area of 2,100 square kilometers, it is the world's biggest habitat and reproduction base of wild red-crowned cranes.

It is also home to many other rare bird species, including eight species under national first-class protection.

China has been stepping up efforts to protect wetlands.

In June, the country's new law on wetland protection took effect.